TV-Series
Description
Hajime Mutsuki is the male representative for the month of January and the leader of the idol unit Six Gravity. He is a character defined by a powerful natural charisma and a commanding presence that often places him at the center of any group without him even realizing it. Many of his peers and acquaintances hail him as a "King" not only because of this personal appeal but also because he is genuinely good at taking care of those around him.

Coming from the noble Mutsuki family, Hajime possesses high intellect and was the top student at a prestigious all-boys private school known as one of the top schools in Japan. He is also highly proficient in English. Despite his privileged background and numerous talents, he remains grounded and does not let his accomplishments go to his head. In conversation, he is a man of few words, and while he can be quite blunt, sarcastic, and severe at times, his intentions are always well-meaning. He holds a strong dislike for doing things half-heartedly or leaving them incomplete.

Beyond his intellectual gifts, Hajime also possesses remarkable physical strength. This is most famously demonstrated through his "Iron Claw" technique, which gives him the power to crush an apple with his bare hands. He has also practiced martial arts and self-defense. He has a soft spot for animals and people younger than him, and he is known to help others with their studies through sessions that are jokingly referred to as the "Iron Claw Cram School" due to his strict teaching methods. Despite his mature and severe exterior, he has a surprisingly childish side that tends to emerge when he is with the senior members of his agency, and he can also be a bit airheaded, making him an occasional target of gentle teasing.

In the story, Hajime is discovered as a potential idol alongside his close friend and classmate, Yayoi Haru. The two of them are the first to move into the Tsukino dorms after being scouted. As the leader of Six Gravity, he acts as a pillar of support for his unit members. His most significant relationship is with Haru, his only companion with whom he feels completely at ease and has been friends with since their second year of middle school. He also has a notable relationship with Shimotsuki Shun, the leader of the rival unit Procellarum. Shun is a big fan of Hajime, and despite their contrasting personalities—with Shun being more noisy and troublesome—the two leaders get along quite well. He is also a distant relative of Hanazono Yuki, the female representative for January, and the two share a friendly, sibling-like bond.

Hajime experiences gradual development throughout the series. The narrative follows him from his third year of high school, where he is balancing university entrance exams with his new idol activities, into university life. Over time, his workload increases, and he takes on numerous solo jobs, for example as a promoter for a cosmetics brand. The story also reveals small details of his past, such as his history of running away from home during the family's New Year's celebrations. An episode focused on him, titled "The Mutsuki Hajime Expedition," showcases his leadership abilities when he and the other members of Six Gravity and Procellarum are stranded on a resort island after a storm. In this crisis, Hajime and Shun take charge as leaders to investigate the island and find a solution.